There are following technical documents regarding format conversions of XML documents. Patent Document 1 describes a device in which a server converts an XML format transmitted from a client and stores it to a cache memory. Patent Document 2 describes a device that converts an XML format already existing as a file according to a definition of XSLT.
Patent Document 3 describes a device that converts an XML format according to XSLT acquired from an XSLT managing server and outputs it via a network. Patent Document 4 describes a processing device that is capable of switching output to a shared buffer and outside by an XPath method in XML filtering processing. Patent Document 5 described a device that performs streaming conversion of an XML which does not build a complete object tree within a memory.    Patent Document 1: Japanese Unexamined Patent Publication 2003-271441    Patent Document 2: Japanese Unexamined Patent Publication 2006-018449    Patent Document 3: Japanese Unexamined Patent Publication 2007-018029    Patent Document 4: Japanese Unexamined Patent Publication 2007-034763    Patent Document 5: Japanese Unexamined Patent Publication 2005-535982